Guinness, the dark Irish beer known to generations of drinkers as the "black stuff", is turning red in some pubs this month as the brewer kicks off a trial of the beer first brewed by Arthur Guinness in 1759.
Guinness's owners, the world's largest alcoholic drinks group Diageo, said on Wednesday its new Guinness Red uses a lighter roasted barley for its ruby red colour and less bitter taste, and will be supplied to 142 British pubs.
The beer is already available in some of the pubs, and pints will be pulled by the start of February at all the 142 pubs owned by Mitchells & Butlers, including the O'Neill's Irish pub chain which has a big Guinness demand.
The new red beer will retain the same creamy head of its darker traditional cousin, and also the same 4.1 percent alcohol level and price of the traditional Guinness Draught. It will be brewed at the same St James's Gate Brewery in Dublin.
A Guinness spokeswoman said the traditional black Guinness already has a reddish hue and by using half roasted malting barley the reddish colour is highlighted in the new product.
The trial is expected to last three to nine months, and is one of a number of variants Guinness has trialled. Currently, Guinness mid-strength with an alcohol content of 2.8 percent is on trial in Irish pubs.
Guinness is one of world's top beers and is sold in 150 countries with 10 million glasses drunk every day. Two variants account for 90 percent of the total volume with Guinness Draught sold in Europe, North America, Japan and Australia, and Guinness Foreign Extra Stout sold in Africa, Asia and the Caribbean.